Field of the Invention
The present invention relates to methods for hermetically sealing luminescent nanocrystals, and hermetically sealed nanocrystal compositions. The present invention also provides microspheres comprising luminescent nanocrystals as well as methods of making the microspheres.
Background of the Invention
Luminescent nanocrystals when exposed to air and moisture undergo oxidative damage, often resulting in a loss of luminescence. The use of luminescent nanocrystals in areas such as down-conversion and filtering layers, as well as other applications, often expose luminescent nanocrystals to elevated temperatures, high intensity light, environmental gasses and moisture. These factors, along with requirements for long luminescent lifetime in these applications, often limits the use of luminescent nanocrystals or requires frequent replacement.